Remove mean from numpy matrix

Question

I have a numpy matrix A where the data is organised column-vector-vise i.e A[:,0] is the first data vector, A[:,1] is the second and so on

Answer 1

You can also use matrix instead of array. Then you won't need to reshape:

>>> A = np.matrix([[1,2,3], [4,5,6], [7,8,9], [10, 11, 12]])
>>> m = A.mean(axis=1)
>>> A - m
matrix([[-1.,  0.,  1.],
        [-1.,  0.,  1.],
        [-1.,  0.,  1.],
        [-1.,  0.,  1.]])